Sunday, July 17, 2016

evTD Gets LED Headlights


I'm still trying to get the 12 volt system under control on the evTD. Whenever the cooling fans and pump are running (most of the time here in Texas) and I turn on the headlights, the voltage sags below 12 volts. There's a momentary shudder and error light from the Soleton1 controller due to current inrush to the sealed beam headlights. Even after it recovers, the lighting still seems dim and yellowish and the high beams pull down the voltage further and cause the controller error light to flash. I replaced all of the secondary lights with LEDs a couple of years ago with limited success, so it's time to have a go at the headlights.

I ordered a set of Truck-Lite LED 7 inch round headlights. The prices have come down significantly over the last couple of years, but they are still a bit pricy compared to sealed beams. These are advertised for Jeeps mostly, although they do reference "other classic cars". They have a standard plug connection that is compatible with the old sealed beams and they are an easy and direct replacement.

Here are some before and after photos:

Sealed Beam Headlights

Sealed Beam Pattern
LED Headlights

LED Pattern
I am very pleased with the optics of the new lamps: the light is whiter and more intense than the old sealed beams. It makes night vision much better and I think I'll put a set on the PorschEV just because of the improvement for driving after dark. The voltage sag results are a mixed bag: no more controller shudder when turning on the lights and the voltage holds just above 12 volts with the cooling system running, but with high beams voltage drops below 12 volts and turns on the error light. These lamps are rated for 1.8 amps draw on low beams and 3.6 amps for high beams so at this point I think I need to look at the cooling fans and pump to see if I can cut back on the current draw and subsequent sag they are causing, Stay tuned ...